I flip a few times. I tried flipping just once but I never liked the results so I just went with what works. Glad to see people exposing culinary bullshit.
Just do whatever works and trust your palette, sense of smell, your vision, etc. I do like Gordon but I never listen to people who talk in absolutes. There are always exceptions to any rules. But he teaches a lot of great basic techniques which can change your life. Some people don't know how to fry an egg or cook a steak and it's a travesty. I don't know how people don't know how to cook. You have to eat to live, right? How can people not know how to cook?